Working this week on a project that is a fine example of where I think ST proves itself in the real world. This is a real part to be machined just as soon as I have time after the Huntsville Summit. I remember how long this stuff used to take. The great thing is the design time is a fraction of what it used to be but I still get to charge the same so it is money in my pocket.
Here is todays problem. A bakery is producing muffin batter and needing to fill up to 3,000 buckets a week with product. They do not have a dedicated engineered line set up for this as it is a new product and no one knows what the success will be. As you can imagine existing equipment is being adapted to serve until hopefull success in sales funds the correct equipment.
In the meantime a large depositor that can fill the buckets in two strokes has a really odd valve in it that does not give consistent volume per stroke and is a royal pain to clean each day. The valve body is 6″ x 6″ x 6″ and this is the size needed for the replacement valve. The tubing running to the valve is 3″ sanitary tubing and we need to also work around that size.
Now keep in mind that what I am going to show here is just the editing of a part imported into SE using an .stp file so I am going to be working with a dumb solid. It is however a proven design and all I need to do is change the size to meet our design criteria. Because of the block size I am limited to a 4″ OD 3.85″ ID tube size for the block product feed holes. The existing opening on the valve type I am going to copy is 2.75″ x 1.75″ and by expanding that opening to a 3.6″x 1.75″ with .375″R corners opening I will have 6.179 sq” open area [this will fit in the footprint of the 4″ end of the reducer] and the three inch tube in the rest of the system measures 6.379 sq” and that is close enough. The new valve block will allow for 4″ to 3″ concentric reducers from the valve to the piping with triclamp fittings and as a design criteria this must be easily cleanable in place if neccessary so no spots for food to hang up in is allowed.
The fiddly math parts were done before altering the part so I know what I need to do and will not be showing that as math is the same for every cad system. Keep in mind that a big part of what I am doing here is the reuse of a proven successfull design and I am preserving the important geometry without having to design it from scratch.
In ST it is easy to make irrelevant geometry go away to get to what is important and that is how I will begin after importing the .stp file.
The single most important thing to remember is to lock your dimensions down as you go to prevent things you don’t want to change from changing when adding new features.